1. Field of the Invention
The present invention relates to the field of optical connection technology. It concerns a connector device for the detachable connection of at least one optical waveguide to at least one optoelectronic component and a method for the assembly of such a connector device.
2. Description of Related Art
For the connection between circuit parts or system parts of complex electronic systems for data transmission and processing, optical connections are increasingly being used, because on the one hand they permit extremely high data transmission rates or bandwidths and on the other hand they are insensitive to electromagnetic influences. For the setting up of connections of this type, optoelectronic transmitting and/or receiving elements, such as LEDs, laser diodes, photodiodes, phototransistors and the like, which convert electrical pulses into optical pulses or convert optical pulses back into electrical pulses and are connected to one another by corresponding optical waveguides, must be provided in the circuit parts to be connected. The optical connections are advantageously intended here to be of a plug-in type, in order to facilitate assembly and maintenance. Required for this purpose are so-called “receptacles”, which are mechanically connected to the optoelectronic components or the printed circuit boards (PCBs) carrying them or comparable supports, and which permit optically adjusted insertion of an optical waveguide plug.
In the past, many solution proposals for connections of this type have been made, mainly based on the idea that the optoelectronic component to be connected is accommodated in a separate housing (for example a metallic TO package or a molded-on plastic housing) and can be soldered to a printed circuit board by electrical connections led out from the housing.
Examples of such connector devices in which the components are accommodated in TO packages are described in U.S. Pat. No. 5,546,490 or U.S. Pat. No. 5,751,878 or U.S. Pat. No. 5,042,891. A modification of these solutions which dispenses with the cap of the component housing is disclosed in U.S. Pat. No. 6,409,398.
Examples of connector devices which are based on optoelectronic components encapsulated with plastic are known from U.S. Pat. No. 4,461,537 or U.S. Pat. No. 5,243,678 (in duplex arrangement) or EP-A1-0 938 006 or EP-A1-1 113 300.
Another solution (U.S. Pat. No. 5,692,083) proposes a one-part connector device with an integrated lens which at one end receives the component arranged on a ceramic plate and at the other end has a drilled hole for the insertion of a ferrule.
Disclosed in DE-A1-199 10 163 is an optical connector in which an attachment onto which the plug of an optical waveguide can be laterally fitted is placed on the actual active optoelectronic module and fixed.
All the solutions from the prior art are based on optoelectronic components that are formed as components which can be independently connected to a housing or a supporting base plate and therefore take up a comparatively large amount of space. With increasing miniaturization of the electronic circuits and increasing packing density in the systems, however, a change is taking place in favor of placing optoelectronic components in the form of chips directly on the respective circuit board and connecting them.
An example of such a component in chip form is a multimode VCSEL chip (VCSEL=Vertical Cavity Surface Emitting Laser) of the AP850 type from Avalon Photonics, Zurich, Switzerland designed for the 850 nm wavelength. Such a chip component has external dimensions in the millimeter range and an active surface in the micrometer range.
A connector device for components in chip form arranged directly on the circuit board has been described in various embodiments in U.S. Pat. No. 6,071,017. One embodiment (FIG. 1, 2) has two coaxial sockets, the inner one of which carries an optical element, while the outer one is intended for receiving the ferrule with the optical waveguide. Both sockets must be labouriously adjusted appropriately and separately fixed on the circuit board. Other embodiments (FIGS. 6, 8, 9) are based on a one-piece housing with built-in lens and molded-in ferrule holder. A disadvantage of all these proposals is that receptacles and plug connectors that represent special solutions are specified for the components, so that none of the standardized optical plug connectors (for example of the LC or LX.5 type or the like) can be used for the optical connection.